Combined right and left hand release for packers



. Oct. 20, 1959 K. R. STOHN 2,909,226

COMBINED RIGHT AND LEFT HAND RELEASE FOR PACKERS Filed June 22. 1956 2 Sheets-Sheet l .b 2 5 6 6 .N 8 O O 2 m 2. %M244 4 MHM \0 LWikWllhW-K-W MIAW u 1: -uI H WHVV 3 Y I I n In m1 5 a "I. m... i m R i T. R H A 1 m m K B 3 .76 8 8 8 5 2 6 0 I 6 0 2M 3 3 A 2 1. 1 II 2 l lwll'l 1| 3! II a a l 5 I 6 2 3 ,Q 3 4 K. R. STOHN Oct. 20, 1959 COMBINED RIGHT AND LEFT HAND RELEASE FOR- PACKERS Filed June 22. 1956 2 Sheets-Sheet 2 r, I, r: it!!! l ILEJ.

INVENTOR.

KENDALL R STOHN BY ATTORNEY United States Patent COMBINED- RIGHT AND LEFT HAND RELEASE FORVPACKERS- 1 This invention relates to oil well packing tools, and more particularly such atool having a combined right and left hand release.

It is common practice in the petroleum industry to seal off a portionof a well-bore in order that certain tests may be performed on the surrounding formation, or other operations carried outrwhich aid in evaluating and completing thewell. Packing tools, or packers as they are commonly called, are used to sealthe bore so that fluids may be circulated above and below it for cleaning, cementing or otherwise treating the bore and surrounding formations.

One type of packer which is widely used 'for this purpose is the mechanical packer in which one end of an expandable sealing element is fixed in relation to a stationary element carried by the drill string and a second element movable in the direction of the fixed element is used to squeeze the sealing element and expand it into sealed engagement with the wall of the bore. Many mechanical packers utilize this same basic construction and also require some means for maintaining the packer in inoperative condition until such time as it reaches the point in the bore where the seal is to be made.'

These release devices which are used to hold the packer inoperative while being lowered into the bore and release it at the desired point form the subject matter of the present invention. The packer is'lowered into the bore on the drill string which is -notrotated during the lowering operation. Once the packer has reached the point in the bore where it is to be expanded, the drill rig is used to rotate the drill string in order to operate the release device andexpand-the packer into sealed contact with the Wall of the bore. Despite the fact that the drill string is not rotated whilethe packer is being lowered into the bore, it is well known that the bore itself exerts forces on elements of the drill string in contact therewith which tend to rotate them. Even though the rotational movement imparted to the drill string may be relatively slight, it. is frequently enough to effect premature operation of the release device and expand the packer before it. reaches the desired depth. In nearly all instances, however, the rotational effect of the bore is known and, can be taken into account to prevent untimely actuation of the packer.

In order to compensate for the rotational effect of the bore, a release device is used with the packer which is rendered operative by rotational movement in a direction opposite to that atwhich .thebore tends to rotate it. A right hand packer release device is one which is conditioned for operation by right hand turning of the drill string and a left hand packer release device is conditioned by left hand turning of the string. Thus,a packer having arighthand release device is used in bores which tend to turn the string to the rightand vice versa. The prior art packers having release devices are designed for either right or left hand operation, but not both, and one of each type of packer is thus required to fit all conditions.

It is, therefore, the principal object of the present. invention to provide a combination right and left hand release device for mechanical oil well packers.

A second object of the invention is to provide a com-v bination packer release device which can be easily and quickly conditioned for either right or left hand opera: tion.

' Further objects are, to provide a packer release mechanism that is simple, rugged and ideally suited to use with the conventional oil well drilling and packing elements.

Other objects will be in part apparent and in part pointed out specifically hereinafter in connection with the description of the drawing which follows, and in which:

Figure l is a vertical section through the well bore showing the packer and combination release device of the present invention conditioned for right hand operation and suspended in the drill string as it is being lowered into the casing;

Figure 2 is a view similar to Figure 1 illustrating the invention following conditioning thereof but prior to expansion of the packer;

Figure 3 is a View similar to Figures 1 and 2 showing the packer in expanded sealed position against the casing;

Figure 4 is a fragmentary diametrical section on a larger scale showing the detailed construction of the cage which forms a part of the release device;

Figure 5 is a fragmentary elevation of the cage; and

Figure 6 is a transverse section taken along line 6-6 of Figure 5.

Referring now to Figures 1 through 3 of the drawing, reference numeral 10 represents the ground having a well bore 12 drilledtherein and lined with a casing 14. A portion of the drill string 16 is shown with mandrel 18 connected therein. The mandrel is an elongated member having a passage 20 therein, shownmost clearly in Figure 4, to permit fluid to pass into the bore beneath the mechanical packer, indicated in a general way by numeral 22. The mandrel is attached between hollow sections of the drill string or tubing 16 by a conventional threaded connection such as shown in assembled rela-v tion at 24.

The packer 22 includes a conventional expandable member 26 encircling the mandrel and positioned to be engaged by collar 28 carried by said mandrel in fixed position. Directly beneath the expandable member of the packer is an upwardly and outwardly tapering surface 30 on the mandrel. A plurality of .angularly spaced and transversely aligned slips 32 having their outer surfaces provided with teeth.34 are mounted for longitudinal slidable movement relative to the tapered surface 30. These slips, are each mounted on the upper ends of leaf springs 36, the lower ends of which are attached to the outer barrel 38 of the cage, indicated in a general way by numeral 40. A ring 42 encircles the leaf springs between the slips and cage and acts to hold the slips firmly against the flared surface of the mandrel.

The springs 36 bow outwardly between. the cage and ring and are with the parts as shown in Figure 1 in frictional engagement with the innersurface of the casing and actto retard the downward movement of the cage into the well bore as the drill string and mandrel are lowered therein. The drill stringis, of course, suspended from a drilling rig (not shown) located on the surface at the top of the well bore and is attached thereto for both longitudinal and rotatable movement.

Specifically, in Figure 1 the cage 40 is locked in the inoperative position shown by meanswhich, will be described in detail in connection with Figures 4, Sand 6 as it is lowered into the well bore. As stated, the bowed portions of the springs are in continual slidable engagement with the inner cylindrical surface of the easing during the lowering operation. Also, as aforementioned, the drill string and packer assembly are not intentionally rotated during this lowering operation, although the well bore itself usually tends to impart rotational movement thereto. As will be apparent, the inoperative position of the cage holds the slips on the small end of the tapered mandrel section and prevents the teeth carried thereby from contacting or engaging the casing.

In Figure 2, however, the outer tube or barrel of the cage has been released to upward relative movement on the mandrel. This movement of the outer barrel acts through the springs to slide the slips upwardly along the tapered surface which forces them: outwardly into gripping engagement with the inner cylindrical surface of the well casing. Once the outer barrel has been released for relative movement on the mandrel, such movement is accomplished by lowering the mandrel further' into the bore as the outer barrel remains fixed in relation thereto because of the frictional engagement between the springs and the casing.

In Figure 3 it will be apparent that once the slips are forced outward into gripping engagement with the casing, thus holding the outer barrel of the cage fixed in relation to the bore, further downward movement of the mandrel will force collar 28 carried thereby against the upper end of the expandable member of the packer and squeeze it against the now stationary slips. This action results in the expansion of the expandable member into the liquid tight sealed engagement with the inner surface of the casing. With the packer thus engaged, fluid can be passed into the bore through the hollow drill stem sections and mandrel to accomplish the desired treatment of the well.

Attention is now directed to Figures 4 through 6, inclusive, wherein the cage construction is illustrated. The cage 40 will be seen to include the outer barrel 38, aforementioned, an inner tube or barrel 44, a key 46, a keyway 48, retaining lugs 50, a conditioning lug 52 and a safety lug 54. The inner barrel 44 consists of a tube welded or otherwise permanently attached around the outer surface of the mandrel. A longitudinal slot 56 extends between the upper and lower ends of the inner barrel and a stop 58 is positioned near the upper end thereof across the slot. The length of inner barrel 44 is substantially greater than that of outer barrel 38 which is mounted on said inner barrel in concentric spaced relation, thus forming an annular cavity 60 therebetween. The outer barrel is also mounted for both longitudinal and rotational movement on the inner barrel.

The key 46 is permanently attached to the outer surface of the mandrel near the lower end of the inner barrel and within the slot therein. The key and the slot in the inner barrel are both positioned to extend longitudinally in spaced parallel relation to the axis of the mandrel. The key projects outwardly through the slot beyond the outer surface of the inner barrel and into the annular cavity between the outer and inner barrels, as shown. A continuous annular flange 62, shown in Figure 4, is formed on the upper end of the outer barrel and extends inwardly to the outer surface of the inner barrel. The relationship between the key and the continuous annular flange is such that the outer barrel cannot be removed from the lower end of the mandrel and is, therefore, limited in its downward movement to the point of engagement between said key and flange 62. The lower end of the outer barrel is provided with a non-continuousannular flange 64 containing the keyway 48 sized to pass the key 46. The non-continuous flange also extends inwardly to the outer surface of the inner barrel and will engage the key to stop the upward movement of the outer barrel unless the key is longitudinally aligned with the keyway. When the key and keyway are aligned, however, the outer barrel may move upwardly relative to the inner barrel until the continuous annular flange contacts the stop 58. It is this aligned condition of the key and keyway that is the operative position of the cage illustrated in Figures 2 and 3 of the drawing.

The lower portion of the outer barrel is provided with two angularly spaced, transversely aligned retaining lugs 50, positioned adjacent to, but on opposite sides of, keyway 48. The inner ends of these retaining lugs project inwardly into the annular cavity 60 and the acute angular spacing therebetween is sufficient to pass the key as clearly shown in Figure 6, at the point said key will pass through the keyway. In the particular construction illustrated, the lugs are in the form of a bolt threaded into threaded openings 66 in the outer barrel. The outer barrel is also provided with a second pair of threaded openings 68 which are shown as transversely aligned with one another and angularly spaced, as is the first mentioned pair of openings 66. In addition, each of the openings 66 is longitudinally aligned with one of the openings 68 and are, therefore, positioned adjacent to but on opposite sides of the keyway 48. The single conditioning lug 52 is selectively attached within one of the upper pair of openings 68 and projects inwardly into the annular cavity between the barrels. A third threaded opening 70 is transversely aligned with the lower pair of openings 66, but is positioned in the opposite side of outer barrel. Safety lug 54 is attached within opening 70 and likewise projects inwardly into the annular cavity between the barrels. Each of the lugs 50, 52 and 54 extend inwardly far enough to engage the key when the outer barrel is rotated relative to the inner barrel and the key is positioned beyond or at least within the transverse plane of said lugs.

Conditioning of the release device of the present invention is accomplished by the simple expedient of selectively positioning conditioning lug 52 in one of the upper pair of openings 68 of the outer barrel. The drawings show the lug 52 positioned for right hand conditioning of the release device, which means that the drill string and mandrel must be rotated to the right while the outer barrel of the cage remains substantially stationary in order to effect release of the packer. The only change necessary to prepare the release device for left rather than right hand conditioning is to move conditioning lug 52 into the other threaded opening 68, shown open in Figure 5. For example, if it is known that the well bore will tend to rotate the drill string to the right, the conditioning lug 52 is positioned as shown most clearly in Figure 5 for right hand conditioning. Then the key is arranged so that conditioning lug 52, and also the retaining lug 50 in longitudinal alignment therewith, are positioned between the key and keyway. With this arrangement, as the drill string, packer and release device are lowered into the well bore, the outer barrel of the cage will tend to rotate to the right relative to the mandrel and associated elements which are not rotating, or clockwise as viewed from the surface. Clockwise or right hand rotation of the outer barrel relative to the stationary mandrel and inner barrel will force the key against the conditioning lug 52 and the retaining lug 50 longitudinally aligned therewith without permitting said key to become aligned with the keyway. Actually, therefore, the outer barrel does not, in fact, rotate relative to the inner barrel and mandrel as the key engages the lugs and prevents the relative rotational movement which the bore tends to produce therebetween. Thus it is only clockwise or right hand rotation of the inner barrel and mandrel relative to the stationary outer barrel that will move the key in position to register with the keyway and this is known as right hand conditioning, as has already been mentioned. The particular longitudinal position of the conditioning lug 52in either of the openings 68 relative to the keyway 48 is such that said lug acts to position the key in longitudinal alignment with the keyway when in contact therewith following selected relative rotational movement between either the outer barrel or mandrel and. inner barrel. In the present instance, the key is aligned with the keyway by rotating the drill string, mandrel, inner barrel and key, all of which rotate together, to the right or clockwise, which moves the key through slightly less than a complete revolution until it rests against theother side of lug 52 where it isproperly aligned with the keyway.

Referring now in particular to Figures 1 and 4, the operation of the cage while the packer is being lowered into position will be described. Of course, lug 52 must already be selectively positioned in theproper opening 68 in the manner described above before the assembly is lowered into the bore. As the cage enters the bore the bowed portion of the leaf springs will engage the casing and retard the movement of the outer barrel relative to the mandrel and associated parts. This will force the outer barrel to move upwardly relative to the inner barrel and mandrel until the key engages the non-continuous flange at the lower end of the outer barrel. This is the full line position shown in Figure 4, although the key would not be aligned with the keyway as shown therein at this stage of the operation. With the key at the lower end of the outer barrel it is blocked by the retaining lugs 50 and cannot move into alignment with the keyway by rotating the outer barrel relative thereto in either direction. There is a remote possibility that the drill string might move erratically and place the key in position where it would only have to pass over one of the lugs 50 to enter the keyway prematurely, which could only happen through relative rotation between the outer barrel and mandrel in the direction in which the release device is set -to be conditioned. The key could not enter the keyway from the opposite direction as it would have to pass over conditioning lug 52 and the continuous flange of the outer barrel prevents the'key from being raised this high within the outer barrel. To prevent even this remote contingency from taking place, however, safety lug 54 is positioned between the key and the single lug 52 over which it would have to pass to enter the keyway. Thus, the key would have to pass over both lugs 54 and 50 to enter the keyway in advance of the time it is desired that the packer be expanded.

When the point is reached for expanding the packer, the drill string, mandrel, inner barrel and key are raised slightly in the bore. The outer barrel will remain fixed in relation to the bore while this takes place as the bowed portions of the springs are in frictional engagement with the casing. Raising of the key within the outer bar-rel places the lower end of said key above the retaining lugs 50 and safety lug 54. The amount of this raising is limited by continuous flange 62. The key can then be rotated within the stationary outer barrel by rotating the string, mandrel and inner barrel in the direction in which the release device has been set to be conditioned. Such action places the key in longitudinal alignment with the keyway. This is the dotted line position of Figure 4.

Once the key and keyway are aligned the release device is in operative position to expand the packer. Downward movement of the drill string, mandrel and inner barrel relative to the stationary outer barrel will move the key through the keyway and cause the slips to move outwardly as they slide upwardly on the tapered surface of the mandrel. The teeth on the slips soon engage the inner surface of the casing and maintain the cage in fixed position. It is this position that has been illustrated in Figure 2.

Thereafter, the mandrel, inner barrel and key are moved further down into the bore, causing the collar 28 carried on the mandrel to push down on the expandable member of the packer and force it against thestationary slips, thus squeezing the packer therebetween and expanding it into sealed engagement with the casing, as shown in Figure 3. v

Release of the packer from sealed contact with the from gripping engagement with the casing and move the key back up into the outer barrel until it engages the continuous flange on the upper end thereof. No further rotation of the parts is necessary in order to raise the packer from the bore as the packer and slips cannot operate with thekey engaging the continuous annular 11b of the outer barrel.

' Thus, the combinationright and left hand mechanical packer release of the present invention will be seen to provide a numbenof distinct and important advantages not found in the prior art devices for this purpose. The most important of these is, perhaps, that a single tool replaces the two tools'required for right and left hand conditioning of the packer in the prior art constructions. Also, of considerable importance is the simplicity of design, construction and ,operation of the instant release device when compared with the conventional tools for this purpose. By merely selectively positioning the conditioning lug in one of-the openings in the outer barrel, the release device herein described isconditioned for right or left hand operation. The simple safety features which prevent premature actuation of the packer are likewise of importance and present a considerable advance over the known art.

From the foregoing detailed description of the drawings and the many improved features of the combination right and left hand release packer of the present invention it will be apparent that the several useful objects for which it was designedhave been achieved. Although the invention has been described in connection with the specific form thereof illustrated in the accompanying drawings, it is to be understood that various modifications may be made and the scope of the invention is to be limited only in accordance with the appended claims.

What is claimedis:

1. As an article of manufacture, an elongated cylindrical member, a tubular member mounted on the cylindrical member for bothlongitudinal and rotational movement relative thereto with an annular space therebetween, said tubular member having inturned ends one of which contains a keyway, a key extending laterally from the cylindrical member and projecting into the space between said relatively movable members, said key being carried by the cylindrical member for conjoint movement therewith from end to end of the tubular member, said key cooperating with the inturned ends to limit the relative longitudinal movement between said relatively movable members in both directions except when said key is aligned longitudinally with the keyway, means carried by and extending laterally from the tubular member into said space for preventing alignment of the key with the keyway when said key is in the end of said member having the keyway and said member is rotated relative to the cylindrical member in either direction, and selectively positionable means carried by the tubular member cooperating with the key to effect alignment thereof with the keyway upon selective rotation of said tubular member relative to the cylindrical member when said key is positioned in the end of said tubular member opposite to that having said keyway, said positionable means being movable into either of two positions on said tubular member one of which aligns the key with the keyway upon selective relative rotation of the tubular member in one direction and the other position aligns said key and keyway upon selective relative rotation in the opposite direction.

2. In a release tool for use in expanding a mechanical packer of the class described, means for gripping a well casing when placed therein, two members mounted for limited relative longitudinal and rotational movement, means for operating said gripping means, which is connected for conjoint movement with one of said members, by relative longitudinal movement between said members of the tool, means forming a partof at least one of said members for locking the gripping means in inoperative position when said tool members are in a first relative longitudinal position, and means forming a part of at least one of said members for releasing said gripping means for relative longitudinal movement'into operative position upon relative rotational movement between said tool members in one direction when said members are in a second relative longitudinal position, said release means comprising a key carried by one of said tool members and a lug and keyway carried by the other of said members, said lulg being selectively positionable in its member to engage the key and effect longitudinal alignment thereof with the keyway for either of the two directions of relative rotational movement between said tool members.

3. In a release tool for use in expanding a mechanical ,packer, slip means for gripping a well casing when placed therein, a first and second member mounted for limited relative longitudinal and rotational movement, means interconnecting the first member and slip means for conjoint movement, the second member having means for moving the slip means between gripping and released positions upon relative longitudinal movement between said first and second members, key means carried by the second member, said first member having a keyway therein arranged to be longitudinally aligned with the key first and second members to permit relative longitudinal movement therebetween in the direction to move the slip means from released to gripping position, means carried by the first member for locking the slip means in released position when said first and second members are in one relative longitudinal position, said locking means preventing alignment of the key means and keyway through relative rotational movement between said first and second members in either direction, and lug means carried by said first member cooperating with the key means to effect alignment thereof with the keyway upon relative rotational movement between said first and second members in another relative longitudinal position, said lug means being movable between two, selected positions relative to the first member, one of said positions acting to align the key means and keyway upon relative rotational movement between said first and second members in one direction and the other of said positions aligning the key means and keyway upon relative rotational movement between said first and second members in the opposite direction.

4. In a release tool for expanding a mechanical packer, slip means for gripping a well casing when placed therein, a first and second member mounted for limited relative longitudinal and rotational movement, spring means interconnecting the first member and slip means for conjoint movement to move the slip means between gripping and released positions, said spring means being adapted to provide frictional engagement with the well casing to retard the movement of the first member and slips when lowered therein, key means carried by the second member, said first member having a keyway therein arranged to be longitudinally aligned with the key means in a selected relative rotational position of said first and second members to permit relative longitudinal movement therebetween in the direction to move the slip means from released to gripping position, means carried by the first member for locking the slip means in released position when said first and second members are in the relative longitudinal position in which the second member is moved downwardly relative to the first member, the movement of which is retarded by the engagement of said spring means with the casing, said locking ,means in a selected relative rotational position of said means preventing alignment of key means with the-keyway through relative rotational movement between said first and second members in either direction, and lug means carried by said first member cooperating with the key means to effect alignment th0f with the keyway upon relative rotational movement between said first and second members in a second relative longitudinal position in which the second member is moved upwardly relative to the first. member, the movement of which is retarded by the engagement of said spring means with the casing, said lugmeans being movable between two selected positions relative to said first members, one of said positions acting to align the key means with the keyway upon relative rotational movement between said first and second members in one direction and the other of said positions aligning the key means and keyway upon relative rotational movement between said first and second members in the opposite direction.

5. In a release tool for use in expanding a mechanical packer, a mandrel having a cylindrical portion, a tubular member mounted on the mandrel for relative rotational and longitudinal movement in spaced relation, means for gripping a well casing when inserted therein depending from the tubular member and movable conjointly therewith, means carried by the mandrel acting to urge the gripping means into engagement with the casing upon downward movement of said mandrel relative to the tubular member, key means carried by the mandrel projecting into the space between said mandrel and tubular member, said key means being movable from end to end of the tubular member upon relative longitudinal movement between said tubular member and mandrel, means carried by the tubular member cooperating with the key means to limit the upward movement of the mandrel relative to said tubular member in all relative rotational positions thereof, means carried by the tubular member cooperating with the key means to limit the downward movement of the mandrel relative to said tubular member in all but one selected relative rotational position thereof, stop means carried by the tubular member cooperating with the key means to prevent said key means from being positioned in said one selected rotational position upon relative rotational movement between said tubular member and mandrel in either direction when said key means is positioned adjacent the lower end of said tubular member, and selectively positionable means carried by the tubular member cooperating with the key means to place said key in said selected rotational position upon relative rotational movement between said tubular member and mandrel in one direction when said key means is positioned adjacent the upper end of said tubular member, said positionable means being movable relative to said tubular member into either of two positions, one of said positions elfecting placement of the key means in said selected rotational position upon relative rotational movement between the tubular member and mandrel in one direction, and the second of said positions effecting placement of the key means in said selected rotational position upon relative rotational movement between the tubular member and mandrel in the opposite direction.

6. In a release tool, a mandrel having a key projecting outwardly therefrom, a barrel enclosing the mandrel, and mounted in spaced concentric relation thereto for both rotational and longitudinal relative movement, said barrel having a continuous inwardly extending annular flange on the upper end thereof adapted to engage the key and limit the downward movement of said barrel relative to the mandrel and a non-continuous inwardly extending annular flange on the lower end thereof providing a keyway sized to pass the key upon upward movement of said barrel relative to said mandrel in a single selected rotational position of said barrel relative to said mandrel, two retaining lugs mounted on the lower end of the barrel and positioned adjacent to and one on each side of the keyway, said lugs forming means for preventing alignment of said key and keyway upon relative rotational movement between the mandrel and barrel in by the barrel above the retaining lugs and arranged to engage the key upon relative rotational movement between said barrel and mandrel, said conditioning lug being mounted in the barrel for selective positioning adjacent to and on one side or the other of the key when said key is aligned with the keyway, said conditioning lug providing a stop in either of said selected positions which will engage the key and prevent alignment thereof with the keyway upon relative rotation between the mandrel and barrel in one direction and which will position said key in alignment with said keyway upon relative rotation between said barrel and mandrel in the opposite direction when said barrel has been moved downwardly relative to said mandrel thereby raising said key above the retaining lugs.

7. In accordance with claim 6, a third lug mounted between the two retaining lugs and opposite the keyway in the lower end of the barrel, said third lug forming a stop between said retaining lugs to limit the relative rotational movement of the key with respect to the barrel to less than a 180 degree are when said key is positioned in the lower end of said barrel.

8. -In accordance with claim 6, slip means carried by the barrel for gripping a well casing, said slip means being movable from a released position to an operative position by upward relative longitudinal movement of the barrel relative to the mandrel, said slip means when in operative position forming a fixed abutment against which a packer may be moved to eifect expansion thereof.

9. In a release device for a mechanical packer having an expandable member, a mandrel having a collar and a downwardly tapering section spaced below said collar, the space therebetween being sized to receive the expandable member of a packer, a key carried on the mandrel spaced beneath the tapered section, said key extending in the direction of the length of said mandrel and projecting outwardly therefrom, a tubular barrel mounted on the mandrel for both rotational and longitudinal movement relative thereto in spaced concentric relation, said barrel having an inwardly extending continuous annular flange on the upper end thereof adapted to engage the key and limit the downward movement of said barrel on the mandrel and an inwardly extending non-continuous annular flange providing a keyway on the lower end thereof, said keyway being sized to pass the key when the barrel is moved upwardly on the mandrel in one selected rotational position of said barrel relative to said key and mandrel, two retaining lugs mounted on the lower end of the barrel adjacent to and on opposite sides of the keyway to align said key with the keyway when the key is in one position, said retaining lugs forming means for preventing the key (from entering the keyway unless in the one position where it is positioned therebetween as the barrel is rotated relative to the mandrel with said key adjacent the non-continuous flange, a single conditioning lug carried by the barrel above the retaining lugs and arranged to engage the key upon relative rotational movement between said barrel and mandrel, said conditioning lug being mounted in the barrel for selective positioning adjacent to and on one side or the other of the key when said key is aligned with the keyway, each of the two selective positions of the conditioning lug providing a stop which will prevent alignment of the key with the keyway upon relative rotation between the mandrel and barrel in one direction and which will act to position said key in alignment with said keyway upon relative rotation between said mandrel and barrel in the opposite direction when said barrel has been moved downwardly relative to said mand-rel in order to raise said key above the retaining lugs, a plurality of angularly spaced parallel leaf springs attached to the barrel and extending upwardly therefrom to the tapered surface of the mandrel, portions of said springs being bowed outwardly and adapted to frictionally engage the inner surface of a casing in a well bore when positioned therein, and a plurality of slips having toothed surfaces attached one to each spring on the upper end thereof, said slips providing means for engaging and gripping the casing when the barrel is moved upwardly relative to the mandrel after the key is in alignment with the keyway, said relative movement between the barrel and mandrel acting to slide the slips upwardly along the tapered surface and outwardly into engagement with the casing thus holding said barrel fixed in relation to said casing whereupon downward movement of the mandrel relative to the stationary barrel and slips will cause the collar to move toward said slips and squeeze an expandable member of a packer placed therebetween into sealed engagement with the casing.

10. In a release tool for use in expanding a mechanical packer of the class described, means for gripping a well casing when placed therein, two members mounted for limited relative longitudinal and rotational movement, means for operating said gripping means, which is connected for conjoint movement with one of said members, by relative longitudinal movement between said members of the tool, means forming a part of at least one of said members for locking the gripping means in inoperative position when said tool members are in a first relative longitudinal position, and means forming a part of at least one of said members for releasing said locking means upon relative rotational movement be tween said members in one direction only to permit relative longitudinal movement of said members to cause movement of said gripping means into operative position, said release means comprising selectively positionable cooperating parts carried by said members for selectively limiting the direction of relative rotational movement of said members.

11. A tool as defined in claim 10 wherein the cooperating parts include a key carried by one of said members and a lug and keyway carried by the other of said members, said lug being selectively positionable with relation to said key for controlling the direction of relative rotation of said members which affects longitudinal alignment of said key with said keyway.

12. A tool as defined in claim 10 wherein one of said members carries additional locking means for maintaining said gripping means in inoperative position when said members are in said first longitudinal position.

13. A tool as defined in claim 11 wherein said one member carries two retaining lugs positioned one on either side of said keyway when the members are in said first longitudinal position.

References Cited in the file of this patent UNITED STATES PATENTS 1,803,841 Crowell May 5, 1931 1,912,805 Tilbury June 6, 1933 2,035,637 Crickmer Mar. 31, 1936 2,603,294 Barnes July 15, 1952 

